Researchers at MUSC Children’s Hospital will use a new $3 million grant to study the effects of vitamin D on pregnant women and their babies.

The project’s directors want their findings to shape public policy on the recommended doses of the supplement that mothers-to-be should take.

Dr. Carol Wagner, a neonatologist at MUSC and project director for the new grant, said researchers will examine the role of vitamin D on mothers’ immune systems and teeth, among other areas of their health.

“By the end of the study, we plan to be able to advise pregnant women on the optimal vitamin D intake during pregnancy,” she said.

Researchers will examine how a deficiency influences “poor pregnancy outcomes” such as infections, premature delivery and developmental problems, she said.

Among pregnant women, about 70 percent of blacks, 33 percent of Hispanics and 12 percent of whites are considered vitamin D deficient, previous MUSC research has found.

Deficiencies appear to be spiking among nonwhite women, putting that group at the highest risk of certain problems during pregnancy, the earlier research shows.

That racial disparity “represents a serious public health issue,” Wagner said.

Beginning this fall, Wagner’s group will begin enrolling pregnant women who are between 10 and 14 weeks of gestation to participate in the study, ultimately taking 300 participants.

The women randomly will be assigned to receive either 400 or 4,000 international units of vitamin D (400 is the amount recommended by the Institute of Medicine, the independent, nonprofit authority on a range of public health issues; 4,000 is the amount that appeared optimal in MUSC’s earlier research).

Researchers will compile data on the women’s health both during pregnancy and after birth. The new babies’ health also will be documented, Wagner said. As part of the same study, researchers at UCLA will examine the effects of vitamin D on pregnant mice, she said.

Dr. Rita Ryan, chairwoman of the Children’s Hospital Department of Pediatrics, said the supplement “offers a potentially easy intervention” for problems that can arise during pregnancy. “This work will increase our understanding of how the vitamin D a mother takes in during pregnancy affects the well-being of her baby,” Ryan said.

The grant was provided by the W.K. Kellogg Foundation.